Cam Shaft Actuators & Timing Chain

[johnjely]

Hi ya,

2009 Vibe here, 136k miles (was a fleet car for Eli Lilly), just bought it in December. I've been having some problems, so I wanted to know if anyone else had ever experienced the same. Not being totally mechanically inclined, I hope I'm posting in the right forum section

SO it started with an overheating issue. I replaced the coolant temp sensor, a sending unit, and the thermostat. That part of my Vibe runs beautifully now; the only issue is that the temp gauge is still reading hot. I know this isn't an engine/transmission issue, but have any of you had to deal with faulty/bad gauges? I was told I'd have to replace the entire instrument cluster to fix it. Thoughts?

The REAL question has to do with a horrible grinding/knocking/almost metal-on-metal noise I was experiencing on a cold start. It lasted only a few seconds and was gone until I had to re-cold-start the Vibe. A mechanic friend brought my attention to a TSB/bulletin that had been put out regarding 2009 Vibes, and it described almost exactly what I was experiencing.

Took the car to my friendly neighborhood Curry GMC dealer, they looked at it, and concluded that I needed 2 actuators and the timing chain replaced. I've already given them the go ahead, so moot point about that, but have any of you experienced this issue, the knocking/grinding on a cold start? If so, what did you do to fix it? Did you have to replace actuators and the timing chain? Did whatever you did help the problem, and if so, for how long?

Thanks in advance for all your wisdom and help!

[Caretaker]

there are lots of conversations posted in this forum that you can search on (about 18 and 34 threads down from this one). What I'm scratching my head about is this: There is more than one actuator in the engine??? If so, that might explain why mine is still exhibiting the noise despite THE actuator being replaced. As for your temp gauge, it sounds like a head gasket issue to me. I do hope not.
As you will read in the other threads, some people have had their starter replaced as a result of the grinding noise at cold startup. I followed the Toyota bulletin as you are doing. It hasn't done me any good so far. I'm taking my car back in after contacting GM Customer Service and expanding my already lengthy case file. For the first time, my grinding noise actually happened AFTER the car was warmed up and driven. Normally it is first thing in the morning and when it is cold. I also have noticed some connection to it occuring when it is humid and rainy outside. Not sure what that would indicate.